Skin disinfectants containing one or more lower alcohols are widely known. Disinfectants containing at least about 50 weight percent alcohol exhibit antibacterial efficacy, however the antiviral efficacy of these alcohol disinfectants depends upon the type of virus.
Pathogenic viruses can be classified into two general types with respect to the viral structure: enveloped viruses and non-enveloped viruses. Some well known enveloped viruses include herpes virus, influenza virus; paramyxovirus, respiratory syncytial virus, corona virus, HIV, hepatitis B virus, hepatitis C virus, SARS-CoV, and toga virus. Non-enveloped viruses, sometimes referred to as “naked” viruses, include the families Picornaviridae, Reoviridae, Caliciviridae, Adenoviridae and Parvoviridae. Members of these families include rhinovirus, poliovirus, adenovirus, hepatitis A virus, norovirus, papillomavirus, and rotavirus.
It is known in the art that “enveloped” viruses are relatively sensitive and, thus, can be inactivated by commonly used disinfectants. In contrast, non-enveloped viruses are substantially more resistant to conventional disinfectants and are more environmentally stable than enveloped viruses. Although a number of non-enveloped viruses can be inactivated with relatively high concentrations of formaldehyde, the use of formaldehyde is undesirable because of its toxicity.
The antiviral efficacy of acid-containing disinfectants, and of disinfectants having an acidic pH, depends upon the type of virus. A few non-enveloped viruses, namely rhinovirus, feline calicivirus, and canine calicivirus, are believed to be at least somewhat affected by acid. See Virus Taxonomy: VIIIth Report of the International Committee On Taxonomy of Viruses, Elsevier Science & Technology Books, ISBN 0122499514, 2005, which is hereby incorporated by reference in its entirety. At least one reference suggests that a pH of less than 5 will provide efficacy against rhinovirus, and other acid labile viruses.
However, many non-enveloped viruses are known to be stable at an acid pH. These include Hepatitis A, Poliovirus, Coxsackievirus, Echovirus, Enterovirus, Adenovirus, Rotavirus, Parvovirus, Papillomavirus, and Norovirus. Thus, while acid-containing disinfectants have been reported to have some antiviral efficacy against, for example, rhinovirus, they have insufficient efficacy against other non-enveloped viruses. That is, the efficacy of these acidic disinfectants is narrow and limited.
U.S. Pat. No. 6,080,417 teaches a hand disinfectant that contains from 50 to 60 volume percent lower alcohol, a C3-5 diol, and a synergist selected from hydrogen peroxide, alkane sulfonates, and salts of thiocyanic acid.
U.S. Pat. No. 6,034,133 teaches a hand lotion containing a C1-6 alcohol, malic acid, and citric acid that, when applied frequently, is asserted to prevent hand-to-hand transmission of rhinoviruses. The lotion was applied to finger pads and dried. A viral suspension was applied to the same finger pads and allowed to dry for ten to fifteen minutes. The finger pads were rinsed, and a viral titration determined that the rhinovirus had been eradicated.
U.S. Pat. No. 5,043,357 teaches virucidal composition containing at least 70 weight percent ethanol and/or propanol, and from 1-5 weight percent of a short-chain organic acid. The virucidal composition is stated to have broad spectrum antiviral efficacy after periods of treatment of at least 1 to 2 minutes. The skin to be disinfected must first be treated to remove skin fats before the antiviral composition is applied.
U.S. Pub. App. No. 2002/0165278 A1 teaches a method for inactivating viruses comprising contacting the virus with a virucidally effective amount of a composition consisting essentially of a dilute aqueous solution of from 0.2 to 13 volume percent C1-3 monohydroxy alcohol or a C2-4 diol, and a sufficient amount of acid to adjust the pH to below 4.6. At these relatively low levels of alcohol, this composition would not be expected to have rapid antibacterial efficacy.
U.S. Pub. App. No. 2005/105070 A1 teaches an aqueous antimicrobial composition stated to have antiviral efficacy against rhinovirus, rotavirus, coronovirus, and respiratory syncytial virus. The composition includes up to 70% of an organic acid and up to 40% of a specific short-chain anionic surfactant having at least one of a large hydrophilic head group, a branched alkyl chain, or an unsaturated alkyl chain. The composition was tested for antiviral efficacy for periods of from 1 to 10 minutes. These relatively high levels of acid and anionic surfactant would be expected to be irritating to the skin, and would not be suitable for leave-on type antiviral products.
U.S. Pub. App. No. 2004/101726 A1 teaches a composition comprising from 10 to 30 volume % alcohol, from 10 to 30 volume % of a long-chain alkyl polyamine, and a halogen, such as iodine. The composition is stated to have antiviral efficacy, and was tested against poliovirus for periods of from 5 to 60 minutes. No testing of other non-enveloped viruses was reported. Also, there was no indication of contact periods of less than 5 minutes.
International Pub. App. No. WO 2001/28340 teaches an antimicrobial composition stated to have antiviral efficacy, although no test data was reported. The composition comprises a dicarboxylic acid, a metal salt, and a dermatologically acceptable carrier. Suitable metal salts include those of metals of Group I, II, IA, IV, VIB, VIII, rare earth compounds, and combinations thereof.
None of the aforementioned publications teaches methods that have broad, fast efficacy against non-enveloped viruses. Each is either limited in its spectrum of antiviral activity or requires long contact times. Therefore, it would be desirable to have a method that achieves a high level of inactivation of non-enveloped virus particles in a short amount of time. A need continues to exist for a method for rapidly inactivating most, if not all, viruses. Furthermore, a need exists for alcoholic compositions that have bacteriocidal and virucidal efficacy and may be used topically against a broad spectrum of enveloped and non-enveloped viruses. In addition, there is a need for an antiviral composition that does not require toxic, regulated, or sensitizing components.